Well pumping unit



Dec. 19, 1933.

c. J. woLFF 1,939,751

WELL PUMPING UNIT Filed 001'.. 5, 1932 2 Sheets-Sheet l l'llllI @Hm/Man Dec. 19, 1933. c. J. woLFF 1,939,751

WELL PUMPING UNIT Filed Oct. 5, 1952 2 Sheets-Sheet 2 Sme/nm Patented Dee. 19, 1933 UNITED STATES PATENT OFFICE This invention relates to improvements in well pumps, and more especially to a novel well pump 1 of the type which employs the well liquid as a Dumping agent.

- The purpose of the invention is to improve the present methods of producing oil; eliminate the necessity of high pressure compression Vplants and their hazards; cut' operating and upkeep costs to a fraction of what they now average; greatly reduce the initial outlay for surface equipment; and at the same time obtain more satisfactory production results than are otherwise obtained.

Another object of the invention is to provide a novel pumping unit which may be inserted in a tubing string in substitution for one of the ordinary tubing sections.

With the foregoing objects outlined and with other objects in View which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in the accompanying drawings, and more particularly pointed out in theappended claims.

In the drawings,

Fig. 1 is a view partly in elevation and partly in section of complete well pumping equipment including one of my improved pumping units.

Fig. 2 is a vertical sectional view of one of my pumping units.

Figs. 3, 4, 5 and 6 are transverse sectional views of the pumping unit taken respectively on the lines 3 3, 4-4, 5--5 and 6-6 of Fig. 2.

Referring to the drawings, 7 designates the casing and 8 the tubing of a well. The annular chamber 9 between these partsis closed at its upper end by a casing head 10, and at the lower end by any suitable seal or packer 11. Oil which is forced up the tubing passes through a pipe 12 into a flow tank 13, and some of this liquid may be forced by a pump 14 into the chamber 9 for the purpose of pumping the well.

In accordance with my invention, a special pumping unit 15 is arranged in the tubing string in place of one of the usual tubing or coupling sections. This unit includes an upper member 16 having upper 'external threads for connection to one of the tubing sections as shown at 17. A partition wall 18 extends horizontally across the tubular member 16 and is provided with one or more bolt holes19, and one or more orifice tube holes 20. The member. 16 has a skirt 21 which is threaded into the upper end of a tubular shell or jacket 22.

Bolts 23 which pass through the holes 19, have threads 24 at their lower ends engaging threaded holes in the top or head 25 of a lower tubular member 26. Said head also has orifice tube apertures 27 corresponding in number to 0 the holes 20. These apertures receive the upper and lower ends of orice tubes 28, each of which khas a chamber 29 at its lower end with a threaded wall to receive the external threads of an adjustable thimble 30 which is held in place by a threaded lock ring 31. 'I'he thimble consists of a cylindrical wall and a head having an aperture 32 at its center. This aperture is in alignment with a short throat 33 at. the medial portion of the tube, which leads into'an upwardly flared passageway 34. Each orifice tube has its portions between the parts 18 and 25 arranged in a chamber 35 which is filled with the well liquid when the device is placed in the well, and the chambers 29 of the orice tubes communicate with the chamber 35 by means of radial ports 36 arranged in each orifice tube.

Each adjustable thimble 30, by careful and accurate shop tests, is positioned so that the smallest area of the vena contracta of an upwardly moving jet of liquid passing through the hole 32 will be opposite the center of the radial openings 36. When the thimble is so positioned, it is firmly locked in place by the nut or threaded ring 31. This is done before the orifice tube is passed to assembly.

Gaskets 37 are preferably placed between shoulders, at the upper and lower end portions of each orifice tube, and the partitions 18 'and 25, to prevent leakage.

It will be noted that the tubular wall ofithe member 26 is of less external diameter than the inside diameter of the shell 22, so that an annular space 38 is provided to permit the well liquid to enter the chamber 35. y

'I'he lower end of the member 26 is sealed by a threadedplug 39 having a valve cage 40 depending from the same. This plug seats on an annular wall 4l having ports 42 to allow the well fluid to enter the annular space 38. The wall 41 is integral with a valve seat 43 which cooperates with a ball valve 44 and is threaded into the lower end of the shell 22. A lock nut 44a is employed to hold the seat in position. The threads 45 at the lower end of the shell are employed in connecting a lower section of tubing 46 to the unit.

The liquid employed for pumping purposes enters an approach chamber 47 of the unit through short tubes 48 which form threaded connections between the parts 22 and 26, and are preferably brazed to the part 22 to prevent leakage.

In assembling the. parts of the unit, the lower member 26 is placed in an upright position and copper gaskets 37 are fitted about the holes 27. Then the orifice tubes 28 have their lower ends inserted in the holes 27. Now the member 16 is placed over the tops of the orifice tubes and the partition 18 is brought to rest on the gaskets 37 on the shoulders at the upper ends of the orince tubes. Then the bolts 23 are inserted and screwed into the partition 25 of the lower member. Now the plug 39 is screwed into the bottom of the member`26. This much of the assembly is now lowered into the upper end of the case or shell 22, and the threads on the part 21 are screwed into the threads at 'the' upper end of the shell to make a leak-proof joint. Then the ball valve 44 is placed in its cage, and the valve seat 43 is screwed into the case until the end of the wall 41 bears against lthe plug 39. Afterwards, the lock nut 44-is inserted.

It will be noted at this point that the assembly is complete except for the passageways between the approach chamber 4'7 and the exterior of the tubing. From the outside of the case 22, opposite the approximate middle oi' the approach chamber, holes are drilled through the case 22,and wall 26. 'Ihe walls of these holes are then threaded and the tubes 48 are screwed into position. Finally, the outer ends of these tubes are brazed to the case.

In use, this pumping unit is put in the tubing string in place of a regular coupling, and it is arranged as near the bottom end of the string as desired, but it must be at some point below the static head of the well when the tubing string is set. Said string is set on a lead seal, or a packer 11 may be used. The tubing string is -connected in a leak-proof manner through the casing head 10, and opens into a ow tank 13 of appropriate size. From the flow tank, a suitable connection is made to the circu- 4 lating surface pump 14, and from this pump,

connection is made into the chamber 9.

The well liquid at such time will be above the pumping unit 15 and hence the chamber 35 is ilooded with well fluid., Ball valve 44 at such time is lightly resting on the valve seat because the weight of the liquid above the ball and the rock pressure of the well from below the ball balance at this level.

It is necessary to have the well full of liquid to operate. A suitable liquid, such as oil or water, or both, is introduced into the well through the circulating pump 14. Each additional pound (per square inch) of such liquid causes the ball valve to seat that much tighter because the weight above the ball valve is that amount greater than the rock pressure of the well below said valve. 'Ihe ball valve eil'ectively shuts off all extraneous pressure from the producing strata, and this is animportant item in my present pump.

There should be enough liquid in the flow tank to cover the pipe connection to the circulating surface pump after the well is full of liquid.

Now the circulating pump is started, and it forces liquid into the well casing exterior of the tubing. As soon as any liquid is forced into the well, immediate action takes place in the pump unit because the liquid`in the annular space between the tubing and casing cannot escape except through the pumping unit and up the tubing string. Hence, the liquid enters the approach chamber 47, thence into the lower ends of the orifice tubes past the sharp edges of the ports 32 and into the throats 33, thence into the flaring discharge passageways 34, and finally up the tubing and into the flow tank. The liquid in passing by the sharp edges of the holes 32, creates areas of low pressure, (approaching a vacuum), at the inner ends of the radial ports 36 in the throat of the tube. Into such areas of low pressure, the well liquid is forced by the rock pressure of the well. Such liquid is pushed upward after it enters the throats of the oriilce tubes, partly by the rock pressure back of it, and partly by contacting the rapid upwardly moving liquid passing throughwthe throats.

VAt the very beginning oi' liquid flow through the orifice tubes, a condition of less than atmospheric pressure tends to develop within the throats of the tubes and would result in a vacuum at the inner ends of the radial ports but for the well liquid rushing into said areas. The ilow of circulating liquid past the sharp edge of each port 32 relieves the pressure at the throat end of the radial ports and, as this occurs, the rock pressure forces the well liquid into the relieved or reduced pressure areas, and simultaneously the ball valve is 'raised from its seat. Such valve has no further action until the well flowing operation ceases, when its own weight, plus the excess of pressure per square inch of liquid in the well over rock pressure, reseats it. It will then remain iirmly seated until the pump 14 is again started.

In flowing liquid from a well in this Way, the liquid is not lifted in the ordinary meaning and use of this word. The weight of the liquid in the tubing to be lifted is balanced or oilset by the weight of the liquid in the casing, and the only actual work done is to overcome the friction caused by moving the liquid. It is easy to circulate the liquid, but the problem is to get the well production into the circulating liquid without pressure reacting on the 'oil producing strata. The orifice tubes get the well liquid into the circulating liquid or outflowing stream. These tubes are accurately proportioned andconstructed on sound principles, and While the well is in operation, will not permit any pressure reaction backward and then downward through openings 4. When operation of the well stops, pressure reaction toward the producing horizon takes place through the radial ports 36, but is immediately stopped by the closing of the valve 44.

While I have shown a pumping unit provided with four oritlce tubes, I intend to use one or more oi such tubes, depending on the amount of liquid the well will produce. In building a pump, if less than four tubes are used, blanks will be substituted to ll up the necessary parts.

From the foregoing it is believed that the construction, operation and advantages of the invention may be readily understood by those skilled in the art, and it is apparent that changes may be made in the details disclosed, without departing from the spirit of the invention, as expressed in the claims.

What I claim and desire to secure by Letters Patent is: f

1. A well pumping unit adapted to be inserted in a tubing string and including an orifice tube having a passageway therethrough, the lower end of said passageway being enlarged and the upper end portion of the passageway ilaring upwardly, said passageway forming a restricted throat between the flaring portion and the enlarged portion, a chamber for well fluid surrounding the orice tube, and radial ports in the tube placing the last mentioned chamber in communication with the passageway of the orifice tube Where the throat is located, said unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid, said radial ports being posihaving a passageway therethrough, the lower end of said passageway being enlarged and the upper end portion of the passageway flaring upwardly, said passageway forming a restricted throat between the flaring portion and the enlarged pcrtion, a chamber for well fluid surrounding the orifice tube, radial ports in the tube placing the last mentioned chamber in communication with the passageway of the orifice tube where the throat is located, and a thimble in the enlarged portion of said passageway having a port in alignment with said throat, said unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid, said radial ports being positioned above said enlarged portion of the passageway.

3. A well pumping unit adapted to be inserted in a tubing string and including an orifice tube having a passageway therethrough, the lower end of said passageway being enlarged and the upper end portion of the passageway flaring upwardly, said passageway forming a restricted throat between the flaring portion and the enlarged portion, a chamber for well fluid surrounding the orifice tube, radial ports in the tube placing the last mentioned chamber in communication with the passageway of the orifice tube where the throat is located, and a thimble in the enlarged portion of said passageway having a port in alignment with said throat, said thimble being adjustable .toward and away from said throat, said unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid, said radial ports being positioned above said enlarged portion of the passageway.

4. A well pumping unit adapted to be inserted in a tubing string and including an orifice tube having a passageway therethrough, the lower end of said passageway being enlarged and the upper end portion of the passageway flaring upwardly, said passageway forming a restricted throat between the flaring portion and the enlarged portion, a chamber for well fluid surrounding the orifice tube, radial ports in the tube placing the last mentioned chamber in communication with the passageway of the orifice. tube where the throat is located, and a thimble in the enlarged portion of said passageway having a port in alignment with said throat, said thimble being adjustable toward and away from said throat, and means for locking the thimble in position, said unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid.

5. A well pumping unit adapted to be inserted in a tubing string and including an orifice tube having a passageway therethrough, the lower end of said passageway being enlarged and the upper end portion of the passageway flaring upwardly, said passageway forming a restricted throat between the flaring portion and the enlarged portion, a chamber for well fluid surrounding the orifice tube, radial ports in the tube placing the last mentioned chamber in .communication with the passageway of the oriflee tube where the throat is located, and an approach chamber for pumping liquid arranged below the orifice tube and communicating with the lower end of said passageway, said .unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid, said radial ports being positioned above said enlarged portion of the passageway.

6. A pumping unit adapted to be positioned in a tubing string, comprising upper and lower tubular members having upper and lower partition walls, said walls having aligned apertures, an orifice tube having its ends extending into said apertures, shoulders on the orifice tube arranged to abut against said walls, means for drawing the walls toward one another for clamping the orifice tube in position, said orifice tube f having a passageway extending through the same, the lower end portion of the passageway forming a constricted throat between the flared and enlarged portions, a chamber between said walls surrounding the orifice tube, and radial ports placing said chamber in communication with the passageway where said throat is located, said unit having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid.

' '1. In a pumping unit of the kind described, a case, an approach chamber in the case, a plug closing the lower end of the approach chamber, a valve seat arranged in the case and having a projecting wall bearing against said plug, and a valve cooperating with said seat and arranged between the plug and seat, said case having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid.

8. In a pumping unit of the kind described, a case, an approach chamber inthe case, a plug closing the lower end of the approach chamber, a valve seat arranged in the case and having a projecting wall bearing against said plug, a valve cooperating with said seat and arranged between the plug and seat, and a cage for the valve depending from said plug, said case having inlets for pressure liquid and the liquid to be pumped, and also an outlet for the pumped liquid.

9. A pumping unit comprising upper and lower tubular members having partition walls provided with aligned apertures, a case depending from the upper member and spaced from the lower member to provide an annular passageway, an orifice tube having its ends extending into said apertures, means securing said partitions together, the orifice tube having a passageway extending therethrough and provided at its medial portion with a constricted throat, a chamber communicating with the annular passageway and surrounding the orifice tube, radial ports in the -tube placing said chamber in communication with said constricted throat, a plug closing the lower end of the lower tubular member, the last mentioned member and said plug forming an approach chamber, tubes connecting the case and the wall of the lower member and extending through said annular passageway, a valve seat arranged below the plug and having an upwardly projecting perforated wall bearing against said plug, a valve chamber communicating with said annular passageway through the perforations of the last mentioned wall, and a valve arranged in the valve chamber and cooperating with said seat, said unit having inlets for pressureliquid and the liquid to be pumped, and also an outlet for the pumped liquid.

CHARLES J. WOLFF. 

